Air cleaner fob internal combustion



Jan. 28, 1941. w SHAW 2,229,824

AIR CLEANER FOR INTERNAL COMBUSTION ENGINES Filed Sept. 16, 1939 INVENTOR. MAL/4M, A \5/1AW.

ATTORNEY.

Patented Jan. 28, 1 941 UNITED sfZTEfs A PATENT oF-FIcE AIR CLEANER FOR INTERNAL COMBUSTION ENGINES William A. Shaw,-'Denver, Colo. Application September 1 6, 1939, Serial No. 295,209

3 Claims.

which will create no obstruction to the flow of the intake air.

Heretofore cleaners of the centrifugal dry dust 10 type or whirl" type were made as shown in applicants prior Patent No. 2,155,911. These cleaners were not uniformly successful. Occasionally cleaners which were low in efficiency when new would be found to be ,very eflicient after several 15 months of use. Upon examination it was found that the unsuccessful cleaners had misformed passages or accidental obstructions such as small drops of adhering solder in the'passages. These irregularities, however slight, would disturb the 20 smooth uniform flow of the air and create whirls, or eddy currents in the air stream which would interfere with the deposition of the foreign particles. After months of use these obstructions would become worn away by the abrasive effect of 25 the dust laden air stream to produce an eflicient passage and an efficient cleaner. Y v

Another object of the invention is to provide a process for designing and finishing air cleaners of this type which will initially produce an abso- 30 lutely smooth, stream-lined inner surface for the passage of the air so that no restrictions to the flow-will be possible and so that no eddy currents can be created which would throw the dust and other foreign materials in theair stream so as to 35 be carried through the cleaner. l

Other objects and advantages reside in the detail construction of the invention, which is de-' signed for simplicity, economy, and eillciency.

These will become more apparent from thefolo lowing description.

In the following detailed description of the invention reference is had to the accompanying drawing which forms' a part hereof. Like numerals refer to like parts in all views of the 5 drawing and throughout the description. In the drawing: v

Fig. 1 is a plan view of an improved air conditionr as produced by the process herein recited.

. Fig. 2 is an elevational view thereof.

50 Fig. 3 is a vertical section, taken on the line- 3-3, Fig. 1. v

Fig. 4 is a horizontal cross section looking downward on the line 4-4, Fig. 3.

The improved air conditioner comprises: a tu- 55 bular standard l formed with any desired coupling sleeve ll atits bottom by means of which it maybe attached to the intake of an automotive engine carburetor. The standard l0 supports a bottle-shaped cleaner housing l2 into the bottom of which a removable dirt receptacle I3 is secured. 5 The air enters the cleaner through an intake passage l4 protected by means of a suitable screen l5.

The intake passage [4 opens to a descending spiral, or whirl passage it which discharges into.-. an enlarged whirl chamber I1. From the whirl Chamber, the air rises througha riser passage l8,

thence 'fiows into and downwardly through an outlet passage I!) in the standard III to the en glue. The sides of the whirl chamber ll incline smoothly downward to a dust discharge orifice 20 which communicates through a downwardly depending tube 2l within the interior of the dirt receptacle 13.

It can be readily seen that the heavier than air particles being carried by the air stream 'will be thrown outwardly against the walls of the whirl chamber l1 and will be carried downwardly along these walls by the descending spiral air current flowing around the chamber. The deposition of the foreign materials in the whirl chamber is also facilitated by the sudden expansion of the air therein due to the greater volume of the chamber. This causes all foreign materials to settle downward and the lighter portions thereof will be forced downwardly by the descending whirl oftthe aircurrents until they drop through the discharge orifice into the receptacle The discharge orifice to the receptacle 3 is so :small that no air currents can be created in the receptacle itself. Any disturbance therein, however, is trapped in the annular trapping chamber 22'around the tube 2 I. After much experimentation, it was found that in order to mak a cleaner of this type successful 40 in removing the exceedingly fine dust particles, it was necessary that all abrupt changes in the air flow be avoided, that all pockets other than the whirl chamber itself must be eliminated, and that the air must flow with uniform velocity and'with- 4 out interference through all passages of the cleaner until the whirl chamber is encountered.

.Many attempts were made to design passages which would meet these requirements but owing to the difliculty of locating the path of least resistance to the flow of the air stream withinthe .cleaner, it was diflicult to theoretically design these passages. It was found, however, that the air stream itself could be employed to design, shape and polish passages of maximum emciency.

coating material, such as quick drying "D1100," is

introduced at the intake orifice, of a cleaner 1 having approximately the correct design and finish, by means of a suitable spray gun, positioned as indicated in broken line at 23, while the cleaner itself is connected with a powerful source of suction. It is found that thecoating material builds up in all pockets and in all portions of the passages wherein the air velocity is low.

After an application of the coating material,

powdered emery or similar granular abrasiveis fed into the intake II and drawn through the cleaner by the air suction. The abrasive strikes the walls of the passages at the points where the air stream impinges and grinds away these portions of the passages. It also grinds away all projections to produce a smooth, highly polished surface. After repeated alternate applications of the building-up material and the abrasive material, the air develops a highly polished streamlined passage having a shape and a surface contour of minimum resistance to the flow of the air such as approximated on the accompanying drawing. The abrasive after each application is collected in the receptacle l3.

Cleaners prepared in accordance with the design produced by the air stream as above are highly efllcient in recovering even colloidal atmospheric dust. This efllciency is even further increased by introducing crank-case vapors into the air stream to increase the specific gravity of 4" fiow. The rush of air past the suction tube this specification and in the claims refers to any creates a partial vacuum to draw the cranlr case vapors into the air stream.

The term whirl type" air cleaner as used in cleaner in which the dry dust and foreign materials are separated from the air stream by centrifugal action of the air itself.

While a specific form of the improvement has been described and illustrated herein, it is desired to be understood that the same may be varied, within the scope of the appended claims, without departing from the spirit of the invention.

Having thus described the invention, what is claimed and desired secured by Letters Patent is:

1. A method of reducing the resistance to air fiow in an air whirl type of air cleaner comprising: drawing a. stream of air through said cleaner; and feeding a quick-drying. air-hardening fluid into the air stream so that the fluid will collect and harden in'the pockets of low air velocity in said cleaner.

2. A method of reducing the resistance to air flow in an air whirl type of air cleaner comprising: drawing a stream of air through said cleaner; and feeding a quick-drying, air-hardening fluid into the air stream so that the fluid will collect, fill, and harden in the pockets of low air velocity in said cleaner, thence passing granular abrasive material into the air stream to abrade away the portions of said passages against which the air impinges.

3. A method of reducing the resistance to air flow in air cleaners of the whirl type comprising: causing a stream of air to how through said cleaner; spraying quick-drying lacquer into the air stream as it enters the cleaner for a sufilcient time td-allow the lacquer to build up and fill in the pockets of low air velocity in said cleaner; allowing the lacquer to harden in said pockets; thence passing powdered abrasive material into the air stream as it enters said cleaner to wear away the lacquer of said cleaner to produce a continuously curvated passage wall paralleling at all points the axis of natural air fiow through said cleaner. WILLIAM A. SHAW. 

